U.S. patent number 6,698,733 [Application Number 10/335,293] was granted by the patent office on 2004-03-02 for hydraulic antivibration support.
This patent grant is currently assigned to Paulstra CRC. Invention is credited to Franck Larmande.
United States Patent |
6,698,733 |
Larmande |
March 2, 2004 |
Hydraulic antivibration support
Abstract
A hydraulic antivibration support including a first rigid
connection device having a base and a vertical pin, a second rigid
connection device having a rigid vertical tube, a first elastomer
body connecting the base to the second connection device and able
to support a permanent weight, a second elastomer body fitted
inside the tube. The second elastomer body has two deformable
walls, on both sides of a free passage traversed by the pin,
defining two hydraulic chambers connected together by a throttled
channel.
Inventors: |
Larmande; Franck (Grand Rapids,
MI) |
Assignee: |
Paulstra CRC (Grand Rapids,
MI)
|
Family
ID: |
31715533 |
Appl.
No.: |
10/335,293 |
Filed: |
December 30, 2002 |
Current U.S.
Class: |
267/293;
267/140.5 |
Current CPC
Class: |
F16F
13/08 (20130101) |
Current International
Class: |
F16F
13/04 (20060101); F16F 13/08 (20060101); B60G
011/22 () |
Field of
Search: |
;267/293-294,140.13,140.5 ;248/562,636 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lavinder; Jack
Assistant Examiner: Nguyen; Xuan Lan
Attorney, Agent or Firm: Marshall, Gerstein & Borun
LLP
Claims
I claim:
1. A hydraulic antivibration support adapted to be interposed
between first and second rigid elements undergoing a relative
vibratory motion at least vertically and parallel to a
substantially horizontal first axis, said antivibration support
including: a first rigid connection device adapted to be fixed to
the first rigid element, said first connection device including a
base and a substantially vertical pin extending from the base, a
second rigid connection device adapted to be fixed to the second
rigid element, said second connection device including a rigid tube
having a substantially vertical central axis, a first elastomer
body connecting the base of the first connection device to the
second connection device, said first elastomer body being adapted
for supporting one of the first and second rigid elements, a second
elastomer body which is disposed inside said rigid tube and which
defines therewith at least two deformable hydraulic chambers filled
with liquid and connected together by a throttled channel, said
second elastomer body including at least two deformable walls which
partially define the hydraulic chambers and which are substantially
aligned parallel to said first axis so as to be deformed by the pin
during relative movements of the first and second connection
devices parallel to said first axis, said pin extending in a
substantially vertical free passage defined between said deformable
walls, and said second elastomer body being free to move vertically
relative to said pin without substantially being deformed.
2. A hydraulic antivibration support as claimed in claim 1, wherein
each of said deformable walls includes an inner portion which is in
close proximity to the pin, and which is free to move vertically
relative to said pin.
3. A hydraulic antivibration support as claimed in claim 2, wherein
said pin is disposed in said free passage with a larger play
parallel to a substantially horizontal second axis than parallel to
the first axis, said second axis being perpendicular to the first
axis.
4. A hydraulic antivibration support as claimed in claim 3, wherein
the second elastomer body includes two lateral elastomer bosses
which are adapted to be abutted by the pin parallel to the second
axis for limiting relative movements of the first and second
connection devices parallel to said second axis.
5. A hydraulic antivibration support as claimed in claim 1, wherein
the second connection device further includes a first rigid
strength member on which the first elastomer body is molded, and a
second rigid strength member which is fixed to said tube.
6. A hydraulic antivibration support as claimed in claim 5, wherein
said tube is fitted in the second strength member of the second
connection device.
7. A hydraulic antivibration support as claimed in claim 6, wherein
the first strength member of the second connection device includes
a central hole delimited by a horizontal annular flange which is in
vertical abutment with said rigid tube in the direction of the
base, and said first strength member of the second connection
device further includes a tubular portion of substantially vertical
axis surrounding said flange, said rigid tube being fitted in said
tubular portion.
8. A hydraulic antivibration support as claimed in claim 7, wherein
said first elastomer body includes a lower elastomer boss adapted
to cooperate with said flange to limit a relative vertical movement
of the first and second connection devices toward one another.
9. A hydraulic antivibration support as claimed in claim 1, wherein
the second elastomer body includes at least a vertical boss which
protrudes opposite of the base and which is adapted to cooperate by
abutment with a transverse rigid member fixed to the pin, for
limiting vertical relative movement of the first and second
connection devices apart from one another.
Description
FIELD OF THE INVENTION
The invention relates to hydraulic antivibration supports.
BACKGROUND OF THE INVENTION
More precisely, the invention relates to a hydraulic antivibration
support adapted to be interposed between first and second rigid
elements undergoing a relative vibratory motion at least vertically
and parallel to a substantially horizontal first axis, for
supporting one of the first and second rigid elements and for
damping said vibratory motions along said first axis.
Such hydraulic antivibration supports are known in the art.
For instance, as shown in FIG. 1 of the drawings, one known
antivibration support 1 of this type, which is designed to connect
a first rigid element 2 such as a vehicle body to a second rigid
element 3 such as a vehicle engine, includes a supporting device 4
having first and second connection members 5, 6 which are
respectively fixed to the first and second rigid elements 2, 3.
The first and second connection members 5, 6 are connected together
by an elastomer body 7 having two thick arms 7a, 7b able to
withstand part of the weight of the second rigid element 3.
The elastomer body 7 enables relative movements between the first
and second rigid elements 2, 3 parallel to first and second
horizontal axes X, Y and parallel to a vertical axis Z.
Further, in order to damp the relative movements between the first
and second rigid elements 2, 3 parallel to the first horizontal
axis X, the antivibration support 1 further includes a damping
device 8, which can be seen in more details in FIG. 2.
The damping device 8 includes a rigid ring of metal 9 which may be
fixed for instance to the first rigid element 2 through a bracket
10 and which may be fixed by crimping to a rigid cover 11, itself
fixed to a stud 12. The stud 12 may be itself fixed to the first
rigid element 2 and possibly to a U shaped guide member 13 (FIG.
1).
Further, the damping device 8 includes a rigid plate 14 (FIG. 2)
which is extended, opposite to the cover 11, by a rod 15 parallel
to axis X, said rod being slidingly mounted in guide 13 and
connected, for instance through an antivibration sleeve 15a, to a
bracket 3a which is fixed to the second rigid element 3.
The plate is overmolded by an elastomer membrane 16 which is also
overmolded on the ring 9. An other elastomer membrane 16a is fixed
to the ring 9 inside the cover 11, and the inner space between the
two membranes 16, 16a is separated into two chambers 17, 18 by a
rigid partition 19 including a decoupling membrane 20 and a
throttled channel 21 in communication with the two chambers 17, 18,
said chambers 17, 18 and said channel 21 being filled with a
liquid.
This known antivibration support has the drawbacks of being
expensive and bulky.
A second known antivibration device 30 of the type in question is
shown in FIG. 3.
This second antivibration device of the prior art includes a first
rigid strength member 31 which is fixed to an outer rigid tube 32
and which is designed to be fixed to the first rigid element 2 as
described above.
The antivibration support 30 also includes a second rigid strength
member 33 which may extend longitudinally parallel to axis Y and
which is designed to be fixed to the second rigid element 3 as
described above.
An elastomer body 34 is fitted inside the tube 32 and includes two
thick arms 35 converging upward toward the second strength member
33 so as to be able to withstand at least part of the weight of the
second rigid element 3. The elastomer body further includes two
deformable walls 36 delimiting two hydraulic chambers 37, 38 with
the tube 32. These hydraulic chambers 37, 38 are filled with liquid
and communicate together through a throttled channel 39.
Thus, when the first and second rigid elements 2, 3 undergo
relative horizontal movements parallel to axis X, the second rigid
strength member 33 presses alternately the deformable walls 36 of
the two chambers 37, 38, thus provoking transfers of liquid between
the two chambers, which damps said horizontal movements.
The antivibration support of FIG. 3 has also the drawbacks of being
expensive and rather bulky, specially in the vertical
direction.
OBJECTS AND SUMMARY OF THE INVENTION
One objective of the present invention is to remedy these
drawbacks, for a cost as limited as possible.
To this end, according to the invention, a hydraulic antivibration
apparatus of the type in question includes: a first rigid
connection device adapted to be fixed to the first rigid element,
said first connection device including a base and a substantially
vertical pin extending from the base, a second rigid connection
device adapted to be fixed to the second rigid element, said second
connection device including a rigid tube having a substantially
vertical central axis, a first elastomer body connecting the base
of the first connection device to the second connection device,
said first elastomer body being adapted for supporting one of the
first and second rigid elements, a second elastomer body which is
disposed inside said rigid tube and which defines therewith at
least two deformable hydraulic chambers filled with liquid and
connected together by a throttled channel, said second elastomer
body including at least two deformable walls which partially define
the hydraulic chambers and which are substantially aligned parallel
to said first axis so as to be deformed by the pin during relative
movements of the first and second connection devices parallel to
said first axis, said pin extending in a substantially vertical
free passage defined between said deformable walls, and said second
elastomer body being free to move vertically relative to said pin
without substantially being deformed.
Thanks to these dispositions, the antivibration support is compact
and, since the supporting and damping functions are carried out by
two separate elastomer bodies, the shapes and mounting of these
bodies is rather simple, so that the support can be manufactured at
a reasonable cost.
In various embodiments of the invention, one may possibly have
recourse in addition to one and/or other of the following
arrangements: each of said deformable walls includes an inner
portion which is in close proximity to the pin, and which is free
to move vertically relative to said pin; said pin is disposed in
said free passage with a larger play parallel to a substantially
horizontal second axis than parallel to the first axis, said second
axis being perpendicular to the first axis; the second elastomer
body includes two lateral elastomer bosses which are adapted to be
abutted by the pin parallel to the second axis for limiting
relative movements of the first and second connection devices
parallel to said second axis; the second connection device further
includes a first rigid strength member on which the first elastomer
body is molded, and a second rigid strength member which is fixed
to said tube; said tube is fitted in the second strength member of
the second connection device; the first strength member of the
second connection device includes a central hole delimited by a
horizontal annular flange which is in vertical abutment with said
rigid tube in the direction of the base, and said first strength
member of the second connection device further includes a tubular
portion of substantially vertical axis surrounding said flange,
said rigid tube being fitted in said tubular portion; said first
elastomer body includes a lower elastomer boss adapted to cooperate
with said flange to limit a relative vertical movement of the first
and second connection devices toward one another; the second
elastomer body includes at least a vertical boss which protrudes
opposite of the base and which is adapted to cooperate by abutment
with a transverse rigid member fixed to the pin, for limiting
vertical relative movement of the first and second connection
devices apart from one another.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics and advantage of the invention appear from
the following detailed description of one of its embodiments, given
by way of non-limiting example, and with reference to the
accompanying drawings.
In the drawings:
FIG. 1 is a perspective view illustrating a first antivibration
support of the prior art;
FIG. 2 is a section view of a portion of the antivibration support
of FIG. 1;
FIG. 3 is a section view of a second antivibration support of the
prior art;
FIG. 4 is a perspective of an antivibration support according to
one embodiment of the invention;
FIG. 5 is a vertical section view of the antivibration support of
FIG. 4, taken along line V--V of FIG. 6;
FIG. 6 is a section view of the support of FIG. 5, taken along the
line VI--VI of FIG. 5, and
FIG. 7 is a top view of part of the support of FIG. 4.
In the figures, the same references denote identical or similar
elements.
As shown in FIGS. 4-7 of the drawings, the invention concerns a
hydraulic antivibration support 100 which is adapted to be
interposed between first and second rigid elements 101, 102 (FIG.
5) undergoing a relative vibratory motion along a substantially
vertical axis Z, along a substantially horizontal first axis X and
along a substantially horizontal second axis Y.
The first rigid element 101 may for instance belong to the body or
frame of a vehicle such as an automobile, whereas the second rigid
element 102 may for instance belong to the powertrain of the
vehicle (for instance, the vehicle engine).
The antivibration support 100 includes a first rigid connection
device 103 which is adapted to be fixed to the first rigid element
101.
The first rigid connection device 103 itself includes (see FIGS. 4
and 5):
a rigid base 104, which may for instance be constituted by a metal
plate (made e.g. out of steel) including a substantially horizontal
flat portion 104a extending longitudinally parallel to the second
axis Y between two folded ends 104b which extend substantially
vertically upward; in the example shown in the drawings, said flat
portion 104a may further include studs 104c or similar connecting
members which extend vertically downward and which are adapted to
fix the base 104 to the first rigid element 101 by means of nuts
104d or similar elements;
and a substantially vertical rigid pin 105, for instance made out
of steel, which extend upward along axis Z from a central part of
the flat portion 104a.
The lower end of the pin 105 may be fixed for instance to a raised
central pressing 104e of the flat portion 104a of the base, for
instance by a crimping 107 made at the lower end of the pin, or by
screwing, welding etc.
Besides, the upper end of the pin 105 may further be connected to a
transverse rigid member 106, for instance a flat horizontal plate
which can be made e.g. out of steel. The rigid transverse member
106 may extend longitudinally for instance parallel to axis Y, and
may be fixed to the pin 105 for instance by a crimping 107 of the
said upper end thereof, or by screwing, welding, etc.
The antivibration support 100 further includes a second rigid
connection device 108 which is adapted to be fixed to the second
rigid element 102, and which is disposed over the first connection
device in the example shown in the drawings. The second connection
device could however be disposed under the first connection device
in other embodiments (not shown).
Said second connection device 108 itself includes a first rigid
strength member 109, a second rigid strength member 114 and a rigid
tube 125 centered on axis Z.
The first rigid strength member 109 may be constituted for instance
by a deep-drawn metal plate, made e.g. out of steel, including for
instance two horizontal tabs 110 which are aligned parallel to axis
Y and which are respectively extended toward one another and
downwards by two sloping portions 111 converging toward a
substantially horizontal flat portion 112.
The flat portion 112 has a central deep-drawn tubular portion 112a
centered on axis Z, and said tubular portion 112a is extended
radially inwardly, at its lower end, by a flange 113 delimiting a
central hole 113a.
The second strength member 114 may also be constituted by a
deep-drawn metal plate, made e.g. out of steel, which includes two
tabs 115 superposed respectively on the tabs 110 of the first rigid
strength member 109.
The tabs 115 are extended, one toward the other and downward,
respectively by two sloping portions 116 which converge toward a
horizontal flat portion 117 situated above said flat portion 112.
The flat portion 117 has a deep-drawn tubular portion 117a which is
centered on axis Z and which has the same diameter as said tubular,
portion 112a.
The superposed tabs 110, 115 of the first and second rigid strength
members may be connected to the second rigid element 102 for
instance by screws 118 (FIG. 5) which go through holes 118a (FIG.
4) provided in said tabs 110, 115.
The rigid tube 125, which may be made for instance out of steel,
may be tightly fitted in the tubular portions 112a, 117a of the
first and second rigid strength members, the lower end of said tube
125 bearing vertically in abutment against the flange 113. The
upper end of the tube 125 may further include a radially outwardly
extending collar 125a which bears on the flat portion 117a of the
second rigid strength member.
The first connection device 103 is linked to the second connection
device 108 by a first elastomer body 119 (FIGS. 4 and 5) which is
overmolded and bonded to said first and second connection devices.
In the example shown in the drawings, the first elastomer body 119
includes two thick arms 120 of elastomer which converge upward and
one toward the other parallel to axes Y, Z, and which are able to
withstand at least part of the weight of the second rigid element
102. Thus, the first elastomer body 119 leaves an open space 121
between the two arms 120.
Each arm 120 extends from a lower end which is overmolded and
bonded to one end 104b and to the adjacent part of the flat portion
104a of the base 104, up to an upper end which is overmolded and
bonded to the corresponding sloping portion 111 of the first rigid
strength member 109.
Further, in the example shown in the drawings, the first elastomer
body 119 also includes a layer of elastomer 122 which coats the
upper face of the flat portion 104a of the base between the two
arms 120. This layer 122 may form a lower elastomer boss 123
protruding upward in correspondence with the pressing 104e, said
lower boss 123 being able to cooperate by vertical abutment with
the collar 113 for limiting relative vertical movements of the
first and second rigid elements 101, 102 one toward the other.
Besides, the antivibration support 100 further includes a second
elastomer body 124 which is fitted inside said tube 125 and which
defines a vertical free passage 126 in which extends the pin
105.
The second elastomer body is preferably overmolded on a reinforcing
steel cage 127 which may include for instance two horizontal rings
128 (FIG. 5) situated respectively near the axial ends of the tube
125 and which are connected together by two vertical connecting
arms 129 (FIG. 6) aligned parallel to axis Y.
The second elastomer body 124 includes two deformable walls 130
which are aligned parallel to axis X and which form two pouches
opening radially outwardly. Each of said deformable walls 130
extends radially inwardly up to an inner portion 131 which is in
close proximity to the pin 105 but which is not bonded to the pin,
so as to enable a vertical sliding movement of the pin relative to
the second elastomer body 124 without substantial deformation of
the deformable walls 130.
Since the rigid tube 125 is fitted in tight contact outside the
second elastomer body 124, said deformable walls 130 define with
the tube 125 two tight hydraulic chamber A, B (FIG. 6) which are
filled with liquid and which are connected together through a
throttled channel C (FIG. 5) itself filled with liquid. Thus, when
the first and second rigid elements 101, 102 are submitted to
relative horizontal movements parallel to the first axis X, said
movements are damped by the transfer of liquid between the two
chambers A, B through the throttled channel C.
The second elastomer body further forms two lateral bosses 132
which protrude radially inwardly in the free passage 126 and which
are aligned parallel to axis Y. These lateral bosses 132 are
adapted to cooperate with the pin 105 by lateral abutment, in order
to limit the relative movements of the first and second rigid
elements 101, 102 horizontally parallel to axis Y.
In the example shown in the drawings, the free passage 126 has an
elongated cross section which extends longitudinally parallel to
axis Y and the pin 105 has itself a substantially rectangular cross
section with rounded angles, the cross section of the pin 105
extending longitudinally also parallel to axis Y. Also, in the
example shown in the drawings, the free passage 126 leaves more
play between the pin 105 and the second elastomer body 124 parallel
to axis Y than parallel to axis X.
Finally, the second elastomer body 124 also includes two vertical
bosses 133 which extend respectively the two lateral bosses 132
upward and which are in vertical abutments with the transverse
rigid member 106 for limiting the vertical relative movements of
the first and second rigid elements 101, 102 away from one
another.
Thanks to these dispositions, the function of supporting the second
rigid elements 102 and the function of damping the horizontal
movements parallel to axis X are carried out separately,
respectively by the first and second elastomer bodies. Due to this
separation of functions, the antivibration support has a rather low
cost of manufacture.
Further, the antivibration support 100 is very compact, specially
in the vertical direction.
Finally, it should be noted that the second elastomer body never
works in traction, which a positive impact on its lifetime.
* * * * *